Tension device for shears.



M. A. MIHILLS. TENSION DEVICE FOR SHEARS.

APPLICATION FILED NOV. 19, 1904..

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PATENTED NOV. 21, 1905.

AT A'NEY MERRICK A. MIHILLS, OF HIGHLAND PARK, ILLINOIS.

TENSION DEVICE FOR SHEARS.

Specification of Letters Patent.

Patented Nov. 21, 1905.

Application filed November 19, 1904. Serial No: 233,392.

To all whmn it Weary concern:

Be it known that I, MnRRIoK A. MIHILLs, a citizen of the United States, residing at Highland Park, in the county of Lake and State of Illinois, have invented certain new and useful Improvements in Tension Devices for Shears, of which the following is a specification.

My invention relates to improvements in shears; and the object of my improvements is to provide shears with adjustable mechanism by means of which the tension of the shearblades may be regulated and the cutting edges of the blade kept in constant contact at the point of intersection.

In the drawings, Figure 1 is a View of a pair of ordinary shears equippedwith myimproved tension mechanism; Fig. 2, a view of the opposite side of same with the blades opened and the handles broken away; Fig. 3, a cross-sectional view, taken on an enlarged scale, on the line 3 3 of Fig. 1; Figs. 4 and 5, cross-sectional views showing modified forms of my tension mechanism; Fig. 6, a side View in elevation of a thumb-screw employed in my invention; Fig. 7, a side view in elevation of an exteriorly and interiorly screw-threaded thimble employed in my invention, and Fig. 8 a side view in elevation of a thimble of modified construction.

Referring to the drawings in detail, a represents the cutting member having the handle to receive the fingers, b the cutting member having the handle to receive the thumb, and c the pivot by which the said members are secured together.

The parts just mentioned are equivalent to those in general use and form no part of my invention proper. In the latter, d represents a metal disk or plate hereinafter called a shoe and located in the inner portion of a screw-threaded perforation a, formed in the member a near the pivot c and in the handle end of the member. Said shoe is provided with a central screw-threaded opening and is adapted to engage the adjacent face of the other member.

Screwed into the perforation a in the member a is an eXteriorly and interiorly screwthreaded thimble 0, into which there is screwed a thumb-screwf, provided with a longitudinal opening having a recessed or enlarged portion at its inner end. A screw-bolt h is inserted in the said longitudinal opening in the thumbscrew and has its inner end screwed into the said opening in the shoe. The said screwbolt is adapted to prevent the accidental removal of the thumb-screw. Located in the said recess in the thumb-screw and encircling the said screwbolt is a coil-spring which has its opposite ends bearing against the shoe and the thumb-screw, respectively.

After the several parts of my improved shears have been assembled in the manner shown and described the friction between the cutting edges of the blades may be increased or diminished by adjusting the thumb-screw e, which in turn increases or diminishes the tension of the coil-spring, which in turn increases or diminishes the pressure of the said shoe against the handle end of the cutting member 5. When the said pressure is increased, it tends to separate the handle ends of the members and keeps the cutting edges of the blades in constant contact at the point of intersection.

The thimble 6 increases the depth of the bearing for the thumb-screw and also provides an annular shoulder to keep the shoe in place when the thumb-screw is removed.

In the modified construction shown in Fig. A I eliminate the thimble e and the screw-bolt it and use only the shoe (Z, the spring and the thumb-screw f.

In the modified construction shown in Fig. 6 the shoe is adapted to be engaged by the thumb-screw, which is inserted in a thimble provided on its inner end with an annular flange e engaging an annular shoulder formed on the wall of a plain perforation (4 formed in the member (0.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, 'is

1. In a pair of shears, two cutting members pivotally connected and each provided with a blade and a handle, one of said members having a perforation near the pivot and in the handle end of the member, a shoe located in said perforation adjacent to the other member, an interiorly-screw-threaded thimble arranged in said perforation, a thumb-screw screwed into said thimble and provided with a longitudinal opening, a screw-bolt inserted in the longitudinal opening in the thumbscrew and having its inner end connected with said shoe, and aspiral spring surrounding said screw-bolt and having its opposite ends bear ing against the shoe and the thumb-screw respectively.

2. In a pair of shears, two cutting members pivotally connected and each provided with a blade and a handle, one of said members hav- ITO ing a perforation located near the pivot and between the latter and the handle and formed scribed.

3. In a pair of shears, two cutting members pivotally connected and each provided with a blade and a handle, one of said members having a perforation located near the pivot and between the latter and the handle and formed with an annular shoulder at its outer end, a thimble arranged in said perforation and provided on its inner end with an annular flange engaging said annular shoulder, a screw inserted in said thimble, and a spring located between the screw and the other member.

4:. In a pair of shears, two cutting members pivotally connected and each provided with a blade and a handle, one of said blades having a perforation near the pivot and in the handle end of the member, ashoe located in said perforation, a thimble inserted in said perforation, a thumb-screw screwed into said thimble, and a spring located between the thumbscrew and the shoe for the purpose described.

5. In a pair of shears, two cutting members pivotally connected and each provided with a blade and a handle, one of said members having a perforation near the pivot and in the handle end of the member, a shoe located in said perforation adjacent to the other blade, a thimble removably secured in said perforation exterior of the shoe, a screw adjustably mounted in said thimble, and means connecting the screw with said shoe.

6. In a pair of shears, two cutting members pivotally connected and each provided with a blade at one end and with a handle at its opposite end, one of said members having a perforation near the pivot and in the handle end of the member, a shoe located in said perforation and engaging the other member, ascrew adjustably mounted in the said perforation and provided on its inner end with a recess, and a coil-spring arranged in said recess and engaging the said shoe.

7. In a pair of shears, two cutting members pivotally connected and each provided with a blade at one end and with a handle at its op posite end, one of said members having a perforation located near the said pivot and in the handle end of the member and formed with an annular shoulder at its outer end, a thimble arranged in said perforation and provided on its inner end with an annular flange engaging said shoulder, a shoe lodged in the inner end of the said perforation and engaging the other member, and a screw inserted in the said thimble and having its inner end engaging the said shoe.

In testimony whereof I aflix my signature in presence of two witnesses.

MERRICK A. MIHILLS.

Witnesses:

I. DANKS, O. K. TREGO. 

